"What it make here?" demanded Miranda. "Tied by a rope to the machine--some one use it." The inference, logical enough, certainly, increased Leighton's excitement. That the magnet was known and used by the inhabitants of the cave--if there were inhabitants--was evident. Under certain conditions a bar of metal that could attract gold with such force as that displayed by the Black Magnet would be of untold value. Here, where there were no evidences of mining operations, and attached to this primitive machine, it was difficult to explain what it was actually used for. Leighton, more and more mystified, determined that the best way to solve the puzzle was to operate the machine in the manner indicated by its structure. It was not, as he pointed out--but as they in their first excitement imagined--a gallows. Instead, it was a winch, built in the most simple and archaic fashion; and as the Black Magnet was attached to it, the evident purpose was to hoist that huge body from the ground. Before testing this theory, Mrs. Quayle, who had recovered from her collapse sufficiently to join the others, insisted that her jewelry should be released from the magnet. Suspicious of the intentions of some of her companions, she was determined to regain possession of her treasures at once. But, as it was apparently impossible to wear her jewelry with comfort, or even safety, in the immediate vicinity of the Black Magnet, necklace, brooch and bracelets were removed to a distant corner of the corridor and there placed beneath a pile of stones. This done, the four men started to work the two long handles of the winch. At first these were turned with difficulty, the resistance proving, at least to Leighton's satisfaction, that the machine had not been used for a long time. Gradually, however, the coil of liana was transferred from the ground to the transverse beam overhead until it pulled taut with the magnet beneath. Then came the real trial of strength. The magnet wouldn't budge. Miranda puffed and grumbled over the task, declaring it impossible. The rest stopped and rubbed their arms ruefully. But Leighton was inexorable. Encouraging the others, and keeping them at it, by dint of increased exertion--to which Una brought additional assistance--the great Black Magnet was finally dragged from its moorings and held suspended just above the ground. It formed a perfect cylinder, about four feet long by a foot and a half in diameter, and must have weighed, they estimated, considerably over a ton--ten tons, vowed Miranda. On a winch of modern design this weight would not have been difficult to lift. But the hoisting apparatus they were using lacked the ordinary adjustments for counterbalancing such weights; hence, the muscular force needed proved no small matter. "It take twenty men to lift this magnet," growled Miranda. "Twenty men could do it more easily than four men and a woman, undoubtedly," replied Leighton. "But four can do it."